Preoperative Embolization of Meningiomas: Differences in Surgical Operability and Histopathologic Changes Between Embosphere and N-butyl 2-cyanoacrylate.

Objective: This study aimed to examine whether there is a difference in the difficulty of extirpation after use of Embosphere versus n-butyl 2-cyanoacrylate (NBCA) for the embolization of meningiomas.

Methods: Study subjects were 20 patients with meningioma who underwent embolization using either NBCA or Embosphere from April 2012 to December 2016. The difficulty of extirpation was compared and assessed in terms of objective indices, such as operative duration, perioperative bleeding, and Simpson grade, and in terms of subjective indices such as "impression on operative field" and "hardness of tumors" that the surgeon assessed using 3-point scales (dry, moderate, bloody, and soft, moderate, hard, respectively). Pathologic findings, including ischemia, necrosis, and inflammatory changes, were assessed.

Results: No significant differences were found between the 2 groups regarding the mean values of operative duration (P = 0.27), perioperative bleeding (P = 0.23), and Simpson grade (P = 0.39). On the other hand, there was a significant difference with respect to the "impression on operative field" and "hardness of tumors," with reports of dry (54%; P = 0.034) and soft (81%; P = 0.0001), respectively, in the Embosphere group exceeding those of the NBCA group. The pathologic findings showed that although ischemic change (P = 0.43) and necrosis (P = 0.79) were observed in both groups, perivascular inflammation was observed only in the NBCA group (P = 0.006).

Conclusions: No relative merits were found regarding objective indices, whereas the Embosphere group had superior "ease of extirpation" as reported by the surgeon.